Multiple Sclerosis (MS) is a demyelinating disorder that affects over 350,000 persons in the United States today, with 8,000 new cases reported each year. MS is the most common chronic inflammatory disease involving the nervous system. The majority of people with MS are diagnosed between the ages of 20 and 50, although in rare cases, symptoms may appear in childhood or after age 50. MS is twice as common in women than in men and more frequently diagnosed in Caucasians than other racial groups. The cause of MS is unknown, although there is considerable evidence that it is an autoimmune disease. Although the disease does not result in early death or impairment of cognitive functions, it can cripple the patient by disturbing visual acuity; stimulating double vision; disturbing motor functions affecting walking and use of the hands; producing bowel and bladder incontinence; spasticity; and sensory deficits, such as touch, pain, and temperature sensitivity.
Patients typically are diagnosed based on a combination of patient history and neurologic examination, including magnetic resonance imaging (MRI) of the brain and spinal cord, electrodiagnostic procedures (e.g., evoked potential tests such as visual evoked potentials, brain stem auditory evoked potentials, or somatosensory evoked potentials), and lumbar puncture to look for evidence of immunoglobulin synthesis in the cerebrospinal fluid.
Currently, there is no cure available for MS, so treatment typically involves management of symptoms and treatment of the frequency and severity of relapses. Therapeutics that have been approved since 1993 include interferon-β for use in ambulatory patients with relapsing-remitting MS (Paty et al., Neurology 43:662-667, 1993) (e.g., Betaseron® (recombinant interferon β-1β) and Avonex® (recombinant interferon β1α); glatiramer acetate (Copaxone®) for relapsing-remitting MS; and Novantrone® for secondary progressive and relapsing-remitting disease.